1. Field of the Invention
This invention relates to the field of collapsible light fixtures, and in particular to a light fixture that requires no assembly steps to attach disconnected parts, the fixture arms securely locking in place when simply brought into position.
2. Prior Art
Light fixtures such as assembled chandeliers are inherently wasteful of space in shipping. The fixtures are characterized by a plurality of arms radiating from a central body, each arm being a slender sinuous member adapted for carrying a lightbulb or the like at a distal end. Simply packing an assembled light fixture such as a chandelier in a box wastes a great deal of shipping space because the radiating arms define a large volume. Accordingly, the prior art has arrived at a number of ways for supplying light fixtures in knock-down form, such that the user can assemble the finished product from components in situ. Requiring a user to assembly a light fixture from its parts indeed achieves greater shipping efficiency. However, there are substantial difficulties in requiring users to assemble a light fixture from parts.
A first difficulty relates to making and protecting the electrical connections which are required to conductors from the arms to conductors in the central body. U.S. Pat. Nos. 1,024,809--Sechrist; 3,735,123--Porter, et al; and 1,059,742--Lumley teach devices which are intended to be wired during or immediately before certain mechanical assembly steps, mechanical connection between the light fixture arms and the central body being accomplished after the time the electrical connections are made. This procedure avoids the need for end users to make electrical connections but presents a substantial danger of electrical short or parting of factory-made electrical connections due to tension, because the chandelier arms remain freely movable with respect to the body. The devices of these patents are useful for saving space in shipping, but are demanding of the user to carefully and properly assemble the light fixture without placing undue strain on the connections and without exposing conductors to shorting against the fixture body.
The present invention also involves a form of collapsible arms for light fixtures such as chandeliers. However, with the invention, the electrical connections are made prior to shipping and due to the connection of parts, the connections remain safe. Only limited rotational displacement of the light fixture arms is required to properly position and fix in place the arms after unpacking. With the invention, the connections are protected because the arms are fully and finally mounted but for their rotational alignment to the central body of the fixture. When moved into place the arms lock.
U.S. Pat. Nos. 1,016,317--Benjamin and 3,831,022--Porter et al disclose light fixtures in which pre-mounted arms are collapsed for shipping and are opened outward for use. In Benjamin, four arms are folded over, two on two. In Porter, et al, three arms are folded to one side and two to the other. The light fixtures in these devices achieve an at least partial mechanical connection of the arms to the central body that remains in place during shipping. Accordingly, permanent electrical connections can presumably be made safely at the factory. However, the patents lack a simple means for positively bringing the arms into a fixed position. Instead, structural features requires the user to disassemble the light fixture and perform certain steps to lock the arms in place. More particularly, in Benjamin, a portion of the central housing having outwarding-directed slots is longitudinally displaceable on the central housing. The housing may thus be separated to allow the arms to be folded, and replaced when unfolded, thereby locking the arms at predetermined radial orientation relative to the body, as defined by the slots in the housing. Porter, et al has alternative positioning means including a system of asymetrical nuts that bear against the flat faces of a central polygon to lock the radiating arms in position. In alternative embodiments (FIGS. 14 and 15), Porter et al use an arrangement approaching the longitudinally displaceable central body idea of Benjamin.
The Benjamin and Porter, et al devices are useful for conserving shipping space and are relatively easy to assembly. Nevertheless, they require that the user at least partly disassemble the fixture in order to achieve the required mechanical alignments. This will necessarily expose electrical connections to damage, shorting and the like because tension on the wires and lateral displacement of the wires against the housing are unavoidable. Furthermore, light fixtures of this type are frequently shiny brass articles that are in large part made from sheet metal and are easily dented and/or scratched by any contact. Accordingly, any disassembly and reassembly whatsoever is apt to damage the fixture, particularly if tools are required.
According to the invention, the arms are rotated about their axes to fold the apparatus. The arms are resiliently mounted such that each individual arm need only be rotated a fraction of a revolution back into unfolded aligned position and the arm will automatically lock in that position. When aligned, a pin on one of the arm and body drops into a corresponding positioning hole on the other, defining the aligned position. The invention therefore achieves the objects of folding the arms for efficient shipping, protection of electrical connections, and reassembly without tools. There is no requirement that even a single part be removed and replaced.
Positioning holes have been used in prior art light fixtures for locking the alignment of radiating arms to a central body. This may be achieved by using non-round tube shapes and mating holes, or by providing a means to receive an off-center protrusion or outrigger. U.S. Pat. Nos. 1,587,330--Kahns, et al 3,622,779--Lagin have eccentric holes adapted to receive a protrusion affixed to radiating fixture arms. In Lagin, the protrusion is a tab having rectangular cross-section, fittable into a slot, the tab being affixed to the arm by means of a flanged split tube that is fitted over the arm. Kahns, et al employs a non-round washer, the washer having a protruding pin bent parallel to the longitudinal axis of the arm, to engage an off-center positioning hole. These patents are concerned with assembly steps at the factory or the like using tools, rather than collapsing for shipping. Even if extended to shipping, both the Lagin and Kahns, et al patents require substantial assembly steps by the user in situ. The patents do not teach resilient means seeking proper alignment of the parts, but rather only rigidly-connectable pieces that, once aligned upon assembly and tightened as necessary, will hold correct alignment. Therefore, the devices in these patents do not assist the user is protecting electrical connections, or in achieving assembly of an aligned device without tools and mechanical connection steps.
U.S. Pat. Nos. 285,310--Schaffer discloses a fuel-burning lamp having means for realigning two oppositely-directed flame-supporting elements with respect to a base, such that the flame elements (e.g., candles, oil lamps or the like) can be positioned operatively upright either when the base is set upright or aligned horizontally, for example by attachment to a wall. A splined member attached to the connected arms is urged toward a keyway by means of a spring. Although this patent shows that springs and keys can be used in positioning, it fails to disclose how such a device could be adapted to a situation in which the arms were foldable rather than rigidly attached or how similar means might be useful in the case of electric wires routed to the arms.
Other prior art devices in which light fixtures are made collapsible for shipping or ease of assembly are shown in U.S. Pat. Nos. 1,071,938--McKechnie; 1,796,330--Hotchkin and 2,278,433--Elting. These patents show ways in which other inventors have attempted to solve the problems of collapsible light fixtures.
The invention disclosed and claimed herein is directed to solving some of the same problems as prior art collapsible fixtures. However, the invention solves shipping space problems in a manner that protects electrical connections and requires no actual assembly whatsoever. All the user is required to do is to manually move the arms into alignment, whereupon the product is complete and correct alignments are fixed. The maximum rotation which could ever be required to unfold a collapsed arm is less than a full revolution and the axial displacement of the arms is very small, thereby protecting the electrical wires. A nut compresses a spring resiliently urging each arm into engagement with the central body along axes of the arms. Means are also provided defining a rational detent lockwasher arrangement, resisting loosening of the device even with repeated disengagement and reengagement. The invention allows the arms of the chandelier to be folded flat for shipping, thereby conserving space. The fixture is safely made operative by the least mechanically adept of users.
The device facilitates assembly and also protects shiny brass and sheet metal parts from scratches, dents and the like. The invention is therefore readily useable with replaceable bobeche devices and the like, for example as shown in applicant's prior U.S. Pat. No. 4,590,545.